NewbieTexas -- Don't you dare quit now,!! The Christmas No-Overtime Period is history. Things should settle down.
-- You left out a very important piece of information -- what day did you start in September?
-- If you started in early September and working 6 days a week right from the start, you should be past the 90 days.
-- If you started in late September and working 6 days a week it is quite possible you have not yet reached 90 work days. Maybe in the high 70's or low 80's.
-- How many days have you actually work on your assigned route? As previously posted, repetition, repetition, and more repetition is the key to increasing one's speed in doing the job.
-- Quite possibly manglement doesn't know if you are over or under 90 days yet. Best to keep your own log at home, noting the day, the route worked, when you started the day and when you went home. Not only are you tracking work days, but your work hours to check if you are getting properly paid.
-- If you get tossed on a brand new route, you get ACTUAL time for running it. Unfortunately that is only good for the first day, after that manglement considers you "trained" on the route. Something to remember: If you have not run a route in a year, you get ACTUAL time. You will know for sure as you have been keeping track of the dates and routes you have run.
-- Best not to pester manglement about the 90 work days. The quieter you are when reaching it the better. As a bonus, you can be represented by a union steward should something arise between you and manglement.
-- Don't worry ( too much ) about being told you are "slow". Right there and then ask manglement what the problem is and how to improve. Most likely you will get the "deer in the headlight's" look from manglement and they will probably suddenly remember they have somewhere else to be!
-- If threatened with firing, you can remind manglement the the Post Master General issued an edict in late 2015 that RCA's are to be "kept at all costs". If brave enough, ask manglement what will they tell the Post Master General. The USPS has already spent a good deal of time and money on getting you on the employment rolls back in September, so to suddenly discover you are "slow" at the end of the busy holiday season is ... Sorry, can't find the proper word. Tell manglement that you are being thorough and methodical in your work.
-- A 26+ year veteran on another rural web site posted she was told that she was "slow" as the holiday period ended. You are far from being alone.
-- Besides keeping track of your work day, keep a journal, as suggested above, of what happened each day. I used EXCEL for years and ended up with 44,000 lines of information. I'd sit right up front during Stand-Ups, jotting down what ever manglement said. At first, they didn't like it but they got used to it. Rural and city stewards would ask what was said on such and such day. Note what ever suits your fancy. Weather, late trucks, visits by District personnel, carrier retirement, route postings ( timely or late ), new RCA's reporting in, what ever.
Good luck and stay with the program!