#include<bits/stdc++.h>
#define ll long long
#define fir first
#define sec second
#define pii pair<int,int>
using namespace std;

const int maxn=105;
const int inf=0x3f3f3f3f;

namespace Solve {
	char c[maxn][maxn];
	void main(int tid) {
		ios::sync_with_stdio(false);
		cin.tie(0),cout.tie(0);
		int n,m;
		cin>>n>>m;
		set<pii> all;
		for(int i=1;i<=n;i++) {
			for(int j=1;j<=m;j++) {
				cin>>c[i][j];
				if(c[i][j]=='?') {
					all.insert({i,j});
				} else {
					c[i][j]=c[i][j]=='B'?'1':'0';
				}
			}
		}
		for(int i=1;i<=n-1;i++) {
			for(int j=1;j<=m-1;j++) {
				if(c[i][j]!='?'&&c[i][j+1]!='?'&&c[i][j]==c[i+1][j+1]&&c[i][j+1]==c[i+1][j]&&c[i][j]!=c[i][j+1]) {
					cout<<"NO\n";
					return ;
				}
			}
		}
		queue<pii> q;
		auto ck=[&](int x,int y) {
			if(c[x][y]!='?') {
				return ;
			}
			char ans='?';
			auto ckneq=[&](char c) {
				assert(ans!=c);
			};
			if(c[x-1][y-1]=='0'&&c[x][y-1]=='1'&&c[x-1][y]=='1') {
				ckneq('0');
				ans='1';
			}
			if(c[x-1][y-1]=='1'&&c[x][y-1]=='0'&&c[x-1][y]=='0') {
				ckneq('1');
				ans='0';
			}
			if(c[x-1][y]=='1'&&c[x][y+1]=='1'&&c[x-1][y+1]=='0') {
				ckneq('0');
				ans='1';
			}
			if(c[x-1][y]=='0'&&c[x][y+1]=='0'&&c[x-1][y+1]=='1') {
				ckneq('1');
				ans='0';
			}
			if(c[x][y-1]=='1'&&c[x+1][y]=='1'&&c[x+1][y-1]=='0') {
				ckneq('0');
				ans='1';
			}
			if(c[x][y-1]=='0'&&c[x+1][y]=='0'&&c[x+1][y-1]=='1') {
				ckneq('1');
				ans='0';
			}
			if(c[x][y+1]=='1'&&c[x+1][y]=='1'&&c[x+1][y+1]=='0') {
				ckneq('0');
				ans='1';
			}
			if(c[x][y+1]=='0'&&c[x+1][y]=='0'&&c[x+1][y+1]=='1') {
				ckneq('1');
				ans='0';
			}
			if(ans=='?') {
				return ;
			}
			c[x][y]=ans;
			all.erase({x,y});
			q.push({x,y});
		};
		for(int i=1;i<=n;i++) {
			for(int j=1;j<=m;j++) {
				if(c[i][j]=='?') {
					ck(i,j);
				}
			}
		}
		while(all.size()) {
			if(q.size()) {
				pii p=q.front();
				q.pop();
				ck(p.fir-1,p.sec+1);
				ck(p.fir-1,p.sec);
				ck(p.fir-1,p.sec+1);
				ck(p.fir,p.sec-1);
				ck(p.fir,p.sec+1);
				ck(p.fir+1,p.sec-1);
				ck(p.fir+1,p.sec);
				ck(p.fir+1,p.sec+1);
			} else {
				pii p=*all.begin();
				all.erase(p);
				c[p.fir][p.sec]='0';
				q.push(p);
			}
		}
		cout<<"YES\n";
		for(int i=1;i<=n;i++) {
			for(int j=1;j<=m;j++) {
				cout<<(c[i][j]=='1'?'B':'W');
			}
			cout<<"\n";
		}
	}
}

signed main() {
	int T;
	cin>>T;
	for(int t=1;t<=T;t++) {
		Solve::main(t);
	}
}