how long will a deffered payment be on record

longwalks1

curently considering buying out my gf's ex his half of their mortgage on their family home so he can move on (you prob seen my other post), they both deferred on this mortgage last year, and I'm wondering if i did replace him with a transfer of equity, will other lenders still frown upon me and my gf in a couple of years time when we come to sho paround for another deal? Currently on +1.79% above base rate, but if we wanted to fix it in a couple of years time with another lender, will they still frown upon her and her ex missing payments last year?

Thanks in advance