If your cranks are affected (mine are, as it happens) then you are advised to take your bicycle (or just the cranks, if you’re happy removing them) to an approved Shimano dealer or retailer for inspection. In reality this means basically any decent bike shop. Your cranks will then be inspected for any possible signs of delamination at the bond and if they are deemed unsafe or at risk then they will be replaced. Not every affected crankset will need to be replaced, but if yours is deemed necessary to replace, the immediacy of the replacement however is unknown, as this may well be stock dependant, and given the scale of the number of affected cranks there’s every chance there may be a wait.