Wait or switch......Mortgage interest rates

Hey Reddit!

I know it's all a bit of guess, but what would you do in our position - wait or switch now?

• Currently on an interest only 20yr mortgage at 0.65% above base (therefore 5.9% currently)
• Runs out in 3 years
• 220k mortgage on an 850k house
• Can get onto the HSBC 3.94% 5yr repayment mortgage - meet the LTV and affordability

In my simple mind, if base rates were to reduce in a linear fashion (which is a bit of a guess), then as long as the base rate reaches 3.3% (plus my 0.65% above base) in 1.5 years (half my remaining term), then the overall cost is broadly the same over the 3 yr period?

i.e pay more for 1.5 years, then pay less for next 1.5 years - which cancel each other out.

Of course this relies on interest rates going all the way back down to 1.3% which seems a stretch.

Or maybe just wait it out for the next 6 months - see if interest rates start nudging down a bit before switching