Hi Mervyn and welcome to GoY. Neutral or ericaceous but I hope you are not replanting at this time of year.

As you've mentioned compost, hopefully you mean repotting rather than replanting.The latter suggests you've dug up the plant and are replanting elsewhere in the garden, which wouldn't be great at this time of year. Repotting is fine. I'd use a mix of John Innes No. 2 or 3, depending on the maturity of your tree, and ericaceous.

thank you for your comments did mean repottinh