This is not limited to B-Graves boots, I have been posting up comments on Teemo HomeGuard boots issues for almost 2 months with no replies or even a single reply from Riot that says "hey, we know". The issue is with ANY Lvl 2 boots and the bug effects 90% of my teemo games to the point that I just cannot buy HomeGuard due to the unreliability of them. I have bought them after recalling only to have them not work, I've bought them, they worked the first time, then never again?
When your base is overrun and you recall from doing a BD and your running around in circles at the top of spawn screaming for your HG boots to kick in and they don't it a serious issue. Some may think its minor but when you have mobility boots with homeGuard and your flash is up and an enemy champion has 300hp and is finishing off your inhib.... What should be the easiest kill and an inhib save turns into no kill and an inhib loss. Please fix this Riot. On update 4.19 PLEASE just add a note that says you're aware of the Teemo HomeGuard bug.
I could give so many examples and videos, but all you have to do it play 2 games with Teemo, both buy HG upgrade and feel the frustration.