I'd wait till she has roots again tell her no more bumping the base (unless you can find a foolproof way, if u do please tell me about it lol) do a full head of fine weaves (so a bazillion foils) then the hair that's left out Inbetween the foils spatch the colour she likes (whatever that dark tone is on the pic) if you spatch every single left out hair it will appear equally as dark as light, if you do every other (so miss one left out section Inbetween) it will be more subtle (I think this is the best option for this client) and if you wanted a more subtle look again do every 3rd left out weave