#include <queue>
#include <cstdio>
using namespace std;
typedef pair<int,int> pii;
const int N=103;
queue<pii> que;
int n,m;
char s[N][N];
bool inq[N][N];
bool check(int x,int y){
	if(x<1||x>=n) return 0;
	if(y<1||y>=m) return 0;
	if(s[x][y]==s[x+1][y]) return 0;
	if(s[x][y]==s[x][y+1]) return 0;
	if(s[x+1][y+1]==s[x+1][y]) return 0;
	if(s[x+1][y+1]==s[x][y+1]) return 0;
	int tx=-1,ty=-1;
	if(s[x][y]=='?'){
		if(tx<0&&ty<0) tx=x,ty=y;
		else return 0;
	}
	if(s[x+1][y]=='?'){
		if(tx<0&&ty<0) tx=x+1,ty=y;
		else return 0;
	}
	if(s[x][y+1]=='?'){
		if(tx<0&&ty<0) tx=x,ty=y+1;
		else return 0;
	}
	if(s[x+1][y+1]=='?'){
		if(tx<0&&ty<0) tx=x+1,ty=y+1;
		else return 0;
	}
	if(tx<0&&ty<0) return s[x][y]==s[x+1][y+1]&&s[x+1][y]==s[x][y+1];
	if(inq[tx][ty]) return 0;
	s[tx][ty]=s[2*x+1-tx][2*y+1-ty]^21;
	que.emplace(tx,ty);inq[tx][ty]=1;
	return 0;
}
void solve(){
	scanf("%d%d",&n,&m);
	for(int i=1;i<=n;++i) scanf("%s",s[i]+1);
	while(!que.empty()) que.pop();
	for(int i=1;i<=n;++i)
		for(int j=1;j<=m;++j) inq[i][j]=0;
	for(int i=1;i<n;++i)
		for(int j=1;j<m;++j)
			if(check(i,j)){puts("NO");return;}
	while(true){
		while(!que.empty()){
			auto [a,b]=que.front();que.pop();
			if(check(a,b)){puts("NO");return;}
			if(check(a-1,b)){puts("NO");return;}
			if(check(a,b-1)){puts("NO");return;}
			if(check(a-1,b-1)){puts("NO");return;}
		}
		for(int i=1;i<=n&&que.empty();++i)
			for(int j=1;j<=m&&que.empty();++j)
				if(s[i][j]=='?'){
					s[i][j]='B';
					inq[i][j]=1;
					que.emplace(i,j);
				}
		if(que.empty()) break;
	}
	puts("YES");
	for(int i=1;i<=n;++i) printf("%s\n",s[i]+1);
}
int main(){
	int tc;
	scanf("%d",&tc);
	while(tc--) solve();
	return 0;
}
/*
 * B??BW??B?
 * BWBB?BWBW
 * WWBWBB?W?
 * WBBBB?BBW
 * ?BWBBBBBB
 * B???BBBWW
 * BBBB?W?W?
 * BB??B???W
 */