Speak Bad English Movement?

This ad, for the Speak Good English Movement’s year-long programme to promote good English at gigs, asks:

What are you doing on Wednesdays?

Bad, bad English. What it meant to ask was:

What are you doing on Wednesday?

Since the activity takes place every Wednesday, the most natural question to ask is what the reader is doing this Wednesday. (If she/he is free, she/he might consider heading to Timbre, the venue.) If the intended question was indeed what the reader generally does on Wednesdays, then it should be phrased thus:

What do you do on Wednesdays?

How ironic that much of what currently goes out in the name of ‘good English’ is itself in such execrable English.