if your relays behave strangely in terms of bandwidth seen, than this might be due to the fact that there are less than 3 bw auth votes available.
If you run a fast relay it is capped to 10k cw.
This affects currently the 857 fastest relays.
It also affects "low-consensus" relays. I have a bw=5k relay which almost doubled the amount of traffic, increasing steadily from 14.30 UTC until 19.00 UTC [a.k.a. now]. I assume this is because 5k is a much higher percentage of the total bw now compared to when fast nodes was not capped at 10k and at the same time, 5k didn't "give" me enough traffic to meet RelayBandwidthRate.
~ Stian