..........but I'm starting to think Viabtc is no longer truly offering 100 tx per hour
I think they do.
Here are the latest two blocks mined by ViaBTC. Transactions are sorted by their fee rate in ascending order.
Just visit the above links and see how many low fee transactions they have included.
According to above times, ViaBTC should have accelerated 300 transactions freely in block number 823066.
Let's check if they did so.
The minimum required fee rate for getting confirmation in block number 823066 was around 100 satoshi. ViaBTC included 312 transactions with the fee rate of less than 90 sat/vbyte. Click
here to see all those transactions.
10 out of those transactions were confirmed with CPFP and 302 transactions were accelerated by ViaBTC. (All those 302 transactions meet ViaBTC free accelerator requirements.)