The cog suits each have five levels and progress in this way -
Level 1 - 5
Level 2 - 6
Level 3 - 7
Level 4 - 8
Level 5 - 9
Level 6 - 10
Level 7 - 11 (Promotion to final suit)
Level 8 - 12
Then you continue on and on to Level 50. Originally, the suits only went to Level 12, but when Disney saw how fast people reached Level 12, they increased it. Of course, HQ was much harder back then and you had to get a LOT more merits every time. Suit progression is the same for all HQs so far.
If you look at a guide to merits/bucks/jns either here on on the TT Guide, you will see that they start low at the beginning of each suit and increase to a promotion amount. Once you get that new suit, you start the process again.
Regarding the 2100/420 - that is showing that you did 2100 previously and now need 420. Whenever I see someone with a merit display like that, I know that they just got a suit promotion.
Hope that makes it a bit clearer for you.
