I think they are kind of middling for delivery times
@Ohsewsimple . Maybe about a week or so - not ultra quick if I remember rightly.
No I don't know what too much fabric is either.
For quick postage I find Immanuels the best. You would have to message them via FB to see if they have calico and the price. It's a flat £5 for postage but the parcel arrives the next day. I've messaged them several times about fabric that I think they might have but which isn't't actually on their FB site and it works quite well. Their fabric prices are good.