#include <bits/stdc++.h>
#define endl '\n'
using namespace std;
const int N=1e5+10,M=N<<3;
int dx[]={-1,0,1,0},dy[]={0,1,0,-1};
vector<vector<int>> a,G;
int dp[M][4],pre[M][4],suf[M][4],r,dfn[M];
int posx[8],posy[8],tot,cnt,tim,n,m,fat[M];
int st[M],ed[M],rt[M],stk[M],low[M],dis[M][4];
int getid(int x, int y){return (x-1)*m+y;}
pair<int,int> getpos(int id){
	int x=(id-1)/m+1,y=(id-1)%m+1;
	if (x<1||x>n) return {0,0};
	if (y<1||y>m) return {0,0};
	return {x,y};
}
bool invalid(int x, int y){
	return (x<1||x>n||y<1||y>m||a[x][y]);
}
void add(int u, int v){
	G[u].emplace_back(v);G[v].emplace_back(u);return;
}
void tarjan(int x, int fa){
	int son=0;stk[++r]=x;dfn[x]=low[x]=++tot;
	for (int k=0;k<4;k++){
		auto [i,j]=getpos(x);
		int v=getid(i+dx[k],j+dy[k]);
		if (invalid(i+dx[k],j+dy[k])) continue; 
		if (!dfn[v]){
			tarjan(v,x);son++;low[x]=min(low[x],low[v]);
			if (low[v]>=dfn[x]){
				cnt++;int k;add(x,cnt);
				do{k=stk[r--];add(k,cnt);}while (k!=v);
			}
		}else if (v!=fa) low[x]=min(low[x],dfn[v]);
	}if (!fa&&!son) add(x,++cnt);
	return;
}
void dfs(int x, int fa, int col){
	auto [i,j]=getpos(x);
	st[x]=++tim;rt[tim]=col;fat[x]=fa;
	pre[tim][0]=suf[tim][0]=dp[x][0]=(i==1);
	pre[tim][1]=suf[tim][1]=dp[x][1]=(j==m);
	pre[tim][2]=suf[tim][2]=dp[x][2]=(i==n);
	pre[tim][3]=suf[tim][3]=dp[x][3]=(j==1);
	for (int v:G[x]){
		if (v==fa) continue;else dfs(v,x,col);
		for (int i=0;i<4;i++) dp[x][i]|=dp[v][i];
	}ed[x]=tim;return;
}
void build(){
	tim=r=0;cnt=n*m;
	for (int i=1;i<=n;i++){
		for (int j=1;j<=m;j++){
			if (invalid(i,j)) continue;
			if (dfn[getid(i,j)]) continue;
			int x=getid(i,j);tarjan(x,0);dfs(x,0,x);
			rt[++tim]=0;fill(pre[tim],pre[tim]+4,0);
			fill(suf[tim],suf[tim]+4,0);
		}
	}fill(suf[tim+1],suf[tim+1]+4,0);
	for (int i=0;i<4;i++){
		for (int j=2;j<=tim;j++){
			if (rt[j]==rt[j-1]) pre[j][i]|=pre[j-1][i];
		}for (int j=tim-1;j;j--){
			if (rt[j]==rt[j+1]) suf[j][i]|=suf[j+1][i];
		}
	}return;
}
bool in(int x, int y){
	return (st[x]>=st[y]&&ed[x]<=ed[y]);
}
bool check1(int x, int y, int cut){
	if (rt[st[x]]!=rt[st[y]]) return 0;
	if (in(x,cut)!=in(y,cut)) return 0;
	for (int v:G[cut]){
		if (v==fat[cut]) continue;
		if (in(x,v)&&in(y,v)) return 1;
	}if (!in(x,cut)&&!in(y,cut)) return 1;
	return 0;
}
bool check2(int x, int d, int cut){
	if (rt[st[x]]!=rt[st[cut]]) return dp[rt[st[x]]][d];
	if (!in(x,cut)){
		return pre[st[cut]-1][d]|suf[ed[cut]+1][d];
	}for (int v:G[cut]){
		if (v==fat[cut]) continue;
		if (in(x,v)&&dp[v][d]) return 1;
	}return 0;
}
void bfs(){
	deque<pair<int,int>> que;
	for (int i=0;i<=n*m;i++){
		dis[i][0]=dis[i][1]=dis[i][2]=dis[i][3]=1e9+1;
	}for (int k=0;k<4;k++){
		if (invalid(posx[5]-dx[k],posy[5]-dy[k])) continue;
		int x=getid(posx[4],posy[4]),z=getid(posx[5],posy[5]);
		int y=getid(posx[5]-dx[k],posy[5]-dy[k]);
		if (check1(x,y,z)||check2(x,k^2,z)){
			que.emplace_back(z,k);dis[z][k]=0;
		}
	}while (que.size()){
		auto [x,d]=que.front();auto [i,j]=getpos(x);
		que.pop_front();int pos=getid(i-dx[d],j-dy[d]);
		for (int k=0;k<4;k++){ // 绕
			if (k==d||dis[x][k]<1e9) continue;
			if (invalid(i-dx[k],j-dy[k])) continue;
			int v=getid(i-dx[k],j-dy[k]);
			if (check1(pos,v,x)||check2(pos,k^2,x)){ // 方向相反
				if (dis[x][k]<1e9) continue;
				que.emplace_front(x,k);dis[x][k]=dis[x][d];
			}
		}if (!invalid(i+dx[d],j+dy[d])){ // 推
			int v=getid(i+dx[d],j+dy[d]);
			if (dis[v][d]<1e9) continue;
			que.emplace_back(v,d);dis[v][d]=dis[x][d]+1;
		}else if (i+dx[d]>0&&j+dy[d]>0&&i+dx[d]<=n&&j+dy[d]<=m){
			if (invalid(posx[d^2],posy[d^2])) continue;
			int nx=getid(posx[d^2],posy[d^2]);
			for (int k=0;k<4;k++){
				if (invalid(i-dx[k],j-dy[k])||d==k) continue;
				int v=getid(i-dx[k],j-dy[k]);
				if (check1(nx,v,x)||check2(nx,k^2,x)){
					if (dis[x][k]<1e9) continue;
					que.emplace_front(x,k);dis[x][k]=dis[x][d];
				}
			}
		} // 瞬移到四个点
	}int ans=1e9;
	for (int d=0;d<4;d++){
		int i=posx[7],j=posy[7],x=getid(i-dx[d],j-dy[d]);
		int v=getid(posx[6],posy[6]),z=getid(i,j);
		if (dis[z][d]>=ans) continue;
		if (check1(x,v,z)) ans=min(ans,dis[z][d]);
		if (!invalid(i+dx[d],j+dy[d])) continue;
		if (i+dx[d]<1||i+dx[d]>n||j+dy[d]<1||j+dy[d]>m) continue;
		if (invalid(posx[d^2],posy[d^2])) continue;
		int nx=getid(posx[d^2],posy[d^2]);
		if (check1(nx,v,x)) ans=min(ans,dis[z][d]);
	}if (ans==1e9) cout<<-1<<endl;else cout<<ans<<endl;
	return;
}
void solve(){
	cin>>n>>m;G.clear();a.clear();tot=0;
	G.resize(2*n*m+10),a.resize(n+10);
	fill(dfn,dfn+1+n*m,0);
	for (int i=1;i<=n;i++){
		string s;cin>>s;s='0'+s;
		a[i].resize(m+10);
		for (int j=1;j<=m;j++){
			a[i][j]=(s[j]=='#');
			if (s[j]=='p') posx[4]=i,posy[4]=j;
			if (s[j]=='b') posx[5]=i,posy[5]=j;
			if (s[j]=='=') posx[6]=i,posy[6]=j;
			if (s[j]=='-') posx[7]=i,posy[7]=j;
		}
	}posx[0]=1,posy[0]=(m+1)/2;
	posx[1]=(n+1)/2,posy[1]=m;
	posx[2]=n,posy[2]=(m+1)/2;
	posx[3]=(n+1)/2,posy[3]=1;
	build();bfs();return;
}
int main(){
	ios::sync_with_stdio(0);
	cin.tie(nullptr);cout.tie(nullptr);
	int t;cin>>t;while (t--) solve();
	return 0;
}