Polo rough idle on cold start, idle stumble, etc

[Blitzen]

Can confirm the issue is caused by crap fuel using the APR 98octane Tune,

Filled up last week with United 100 octane, didn't experience any issues all week

Just filled up today with Shell 98, bam, rough idle, rougher to drive, however switched the tune to the APR 95 Octane and its ok, Got a feeling were not really getting 98 octane fuel.

Anyone else noticing this with Shell 98 at the moment?

Edit: after further testing, even on stock tune its still stuttering, bad batch for sure, dodgy bastards

Its funny you say that, but I started noticing it after I got rid of my BP fuel card and using Shell 98... I might throw in a tank of BP Ultimate
When I fill up and see if it still does it.