Hi
The Mortgage Arrears Code applies only to homes, so they cannot use the fact that you are in arrears to move you onto a higher rate.
If you are in breach of your contract on the investment properties by being in arrears, they can restructure the mortgage with a higher rate. were doing this to get people off trackers, but they seem to have suspended their plans.
If you are unable to make your repayments as they fall due, you might have to consider bankruptcy. This would give you a fresh start.
Brendan