Flawless has pretty decent UK EPG.
Dont base your iptv sub choice on epg quality. Go for whatever provider has the best channel lineup and least buffering for you. Then use http://iptv-epg.com for epg data, I use it and I've never found any provider that can match this services accuracy. Their pricing is really good at ~$£€10 per year for 100 channels of epg data etc. No more gaps in my epg!
pretty sure /r/epicstream (epicstream) has full UK EPG (or near complete). They offer a free trial
The best services I have used for English EPG...UK, US and Can... are Vader, Epic and Fab, in that order.
We have a good EPG on mag devices on UKS at www.premiumiptv.co
I just responded to this same question over in another subreddit where I went into a bit more detail.
I'd recommend express if you need UK and timeshifting. However, you won't find a perfect epg unfortunately
Hello, We have UK channels with Full EPG, here is our channel list https://pastebin.com/uNqnvSVp ,PM for free 48hrs trial