Since there are only 5 months left for CAT. How often should I give mocks now and how often should I give them for each of the remaining months.

it's not only about mocks, it about practice, if you will manage to give only 20 mocks in this lat 5 months that will be very helpful..but practice must for different varieties of questions

every weekend once and then shift it to twice a week post 2 weeks and stay consistent with the sectionals Mocks

Depends on which stage of preparation are you, you need to understand how well versed are you in set selection or passage selection or no of attempts and then revise and do mocks, all India rankers give around 50 mocks.