Two-hit medium recovery time
I'm not sure if this is an input/refractor issue or simply happening at the same time, so I'll report it here. Champions with two-hit medium attacks are not able to hit into block reliably. I've attempted it primarily with tigra, who is a solid Apocalypse counter (no attrition masteries), but you need to push him into the corner. Typically, one does that against stun immune apocalypse by hitting into his block, but I tried multiple times and he kept parrying my first light after a double medium. It happened at least 4 times. I also experienced this problem with tigra vs. Peni Parker, and there is no way to avoid hitting into Peni's block.
For my part, iPhone XR, vs. 15.4.1, and maybe 15 minutes of gaming time between starting up and having this problem.
An alliance member experienced this same issue with stealth spiderman vs. Peni Parker.