The good news is it's amazing what you can get away with in terms of catching up.
Though fruit bushes are already sending out leaves, you can still get away with planting them if you're prepared to give them plenty of water in dry weather. If you're strictly a weekend allotmenteer, accept that it is wise to wait and plant in October. You can help get fruitbushes off to a good start, however, by planting with "rootgrow". Helpfully, this is currently on a half-price offer at Hamstreet Garden Centre till the 18th. "Rootgrow" supplies the beneficial mycorrhizal fungi that make the difference between a weedy plant and a vigorous one. You have to use it when planting and cannot add it later.
Click here to go to information about 'rootgrow' and how it works
As far as chitting seed potatoes goes, a study by the RHS found it makes very little difference to the time your spuds crop or the amount they yield. You don't imagine commercial growers lovingly chit them then carefully plant the fragile chitted seed potatoes, do you? If you're late getting away, just plant them as they are, don't wait to chit them!