Money Worries.
F rom your post I take it you are repaying an LTD loan on the strength of you guaranteeing said ltd company.
I am not sure of the way AIB are doing this.
I would be concerned that your 176 is solely being taken as interest and that you are still on the hook forever on the K28.
Suggest;
Write (do not phone) ,keep a copy and ask AIB for a clear breakdown on the account.
In particular ask the question {Is my e176 coming off the principal owed}
If so, your k28 will be paid off in circa 13 years!.
If not your e176 will at best, be stalling matters.
Their reply will allow you to decide on the next move.