Need a bit more info - when you say 'several side shoots from the base of the tree' are you saying the shoots are coming up from below the graft point at the base of the trunk or main stem? If they're coming up from below the graft, you don't want those, they should be removed, but it might mean the tree itself hasn't survived. Peel back a little bark with your fingernail on both trees (on the main stem) - if its brown and dry beneath, its dead. Alternatively, just wait and see - its a bit early, and in some parts of the country, they won't be showing growth yet.

i baught an ornimentle grape vine some years ago about 14 i believe . i knew nothing much about gardening then well trees anyway . it was the only plant in the garden apart from grass . i had know mower at the time and a friend who was working for the council had an industrial strimmer tidying up around the poplers on the green out the front of mine . he said do i want him to do my garden . i said yes please . before i could get a word out he strimmed my cherry tree down below wear it had been grafted .i didnt give it a lot of thaught but it started growing from the root stock as i imagine yours is . its in my front garden on one or two of my blogs . i trained it round my old swing . turned out the root stock grows edible yellow grapes . just wondering if the main tree is dead if its worth seeing what it actualy turns out to be . if you dont like it you can cut it down anyway . as bamboo sais scrape them with your nail . if dead either take the lot out or cut down to the living shoots . just a thaught . i always thaught they coloured red grapes to look yellow lol .