Foe those of us with housing loans, how will we know how much extra to pay, given the rise in OPR?

Example I’m paying rm1,618 now. What do you mean adjust automatically? How will I know how much extra to pay?

May i ask the month instalment will changed based on OPR floating right, but when will the monthly payment amount will change?

because rumor i hear 3 kind of situation, hope i can get an answer from experts

Let said
loan tenure 35year
loan amount 500K
Interest rate will be 2.8% on Loan Offer (sign)
Current OPR increase 0.25% (total in 2%) (3.05%)
feature 5 year let said OPR is 3% (4.05%)

Monthly instalment LO: RM 1868
Monthly instalment currently : RM 1938
Monthly instalment feature 5y: RM 2228

Rumor 1: At current moment (3.05%) monthly instalment we will keep paying RM1868, but the unpaid balance (RM70) will be add into the principle. In result the loan tenure will be extansion more than 35y if all the unpaid balance accumulated year by year.

Rumor 2: The monthly instalment amount will adjusted everytime based on the OPR Floating. In Result the loan tenure can be settled at 35year, but the amount is keep changing everytime OPR change

Rumor 3: The monthly instalment amount will only change within a period based on current OPR let said every 5 year. Mean, since i only paying the LO approval monthly instalment 1868 for five year, after five year the bank will adjust the monthly instalment i need to pay which is 2228. If this one in result, the loan tenure will be extension also, but not longer than rumor 1.

sorry for poor english, but i hope to get the opinion. thank you