Can you imagine how many CVS each airline is receiving at the moment?. .There are plenty of unemployed pilots with Boeing and Airbus ratings and years of experience who are also looking for jobs.. .My tip to you is. .a) don't send 50 CVs a month - follow what a particular airline is doing. If its still shedding staff/ aircraft/ routes they will not want to be receiving CVs.
b) target your experience to the airline. There are publications available which give an indication of the minimum experience required for each airline. No point sending your CV to BA right now for example.
I know you feel you need to do something, but spend the time in preparing for when the market does pick up.
Don't hassle the airlines with a replacement CV every month, that will wind them up. If you have a new rating to add or substantial change in experience then send a new CV for that reason. Otherwise I suggest you limit your CV sending to once every 6 months, or every 3 months for more relevant airlines.