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// Author: Kajetan Ramsza
#include "bits/stdc++.h"

using namespace std;

template<typename F, typename S> ostream& operator<<(ostream& os, const pair<F, S> &p) { return os<<"("<<p.first<<", "<<p.second<<")"; }
template<typename T> ostream &operator<<(ostream & os, const vector<T> &v) { os << "{"; typename vector< T > :: const_iterator it;
    for( it = v.begin(); it != v.end(); it++ ) { if( it != v.begin() ) os << ", "; os << *it; } return os << "}"; }

void dbg_out() { cerr<<'\n'; }
template<typename Head, typename... Tail> void dbg_out(Head H, Tail... T) { cerr<<' '<<H; dbg_out(T...); }

#ifdef DEBUG
#define dbg(...) cerr<<"(" << #__VA_ARGS__ <<"):", dbg_out(__VA_ARGS__)
#else
#define dbg(...) 
#endif

typedef long long ll;

const ll mod = 1e9 + 7;

ll inv_3;

ll power(ll x, ll exp) {
    ll res = 1;
    while(exp > 0) {
        if(exp & 1) {
            res = res * x % mod;
        }
        x = x * x % mod;
        exp /= 2;
    }
    return res;
}

const vector<vector<ll>> add = {
    {1, 0, 0},
    {1, 1, 0},
    {0, 1, 0},
    {0, 1, 1},
    {0, 0, 1},
    {1, 0 ,1}
};

ll calc(ll n, ll m) {
    ll result = power(2, n);
    dbg(n, m);
    dbg(result);
    if(n % 2 == 0) result = (result + mod - 1) % mod;
    else result = (result + mod - 2) % mod;
    result = inv_3 * result % mod;
    dbg(result);
    result += add[n%6][m];
    result %= mod;
    return result;
}

ll n, q;

ll match[2];

ll blue = 0;
ll lit = 0;

ll res() {
    if(n == 1) {
        if(blue == 1) return 2;
        else return 1;
    }
    dbg(blue, lit, match[0], match[1]);
    // 2^blue - calc(blue, (6 - n%3 - lit%3) % 3) - match?
    ll result = power(2, blue);
    dbg(result);
    ll c = calc(blue, (6 - n%3 - lit%3) % 3);
    dbg(c);
    result = (result + mod - c) % mod;
    dbg(result);
    if(n % 2 != 0) {
        if(match[0] + blue == n) result = (mod + result - 1) % mod;
        if(match[1] + blue == n) result = (mod + result - 1) % mod;
    }
    dbg(result);
    return result;
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    inv_3 = power(3, mod - 2);
    dbg(inv_3, 3 * inv_3 % mod);
    cin>>n>>q;
    vector<ll> vec(n);
    
    for(ll i=0;i<n;i++) {
        char c;
        cin>>c;
        if(c == 'N') {
            vec[i] = -1;
            blue++;
        }
        else if(c == 'Z') {
            vec[i] = 1;
            lit++;
        }
        else
            vec[i] = 0;
    }
    
    for(ll i=0;i<n;i++) {
        if(vec[i] == 0) {
            match[i%2]++;
        } else if(vec[i] == 1) {
            match[(i+1)%2]++;
        }
    }
    cout<<res()<<'\n';
    for(ll i=0;i<q;i++) {
        int ind;
        char c;
        cin>>ind>>c;
        ind--;
        if(vec[ind] == -1) blue--;
        else {
            match[(ind + vec[ind])%2]--;
            if(vec[ind] == 1) lit--;
        }

        if(c == 'N') {
            vec[ind] = -1;
            blue++;
        } else if(c == 'Z') {
            vec[ind] = 1;
            lit++;
            match[(ind+1)%2]++;
        } else {
            vec[ind] = 0;
            match[ind%2]++;
        }

        cout<<res()<<'\n';
    }
}