Brp in previous name as old passport,new passport in married

[Nenepep]

Hello,

I cant seem to find the right answer to this anywhere,i have my Brp card in my ex husbands name as that was the name on my passport when i applied for a spouse visa with my present husband, i was granted limited leave to remain but unfortunately my marriage certificate wasn't enough to have them issue my brp card in my current husbands name.

My old passport has now expired, i have now gotten a new one in my husbands name. I will apply to have my name changed to my husbands name on my Brp as it is being used already for my drivers licence and bank account.

My question is can i travel with my Brp and passports at the moment with my marriage certificate as proof
If i exceed the 3 month deadline,by just a few weeks to apply for the change of name on my Brp,do i still have to pay the fine.

Please help,really urgent.

[Nenepep]

Please somebody with information on this,please help