Im, in answer to your 5 questions....no, no, no, waaaaay no, and finally for number 5...it's a no!
Yes Acorn, the look on that Kittys' face with his paw to his mouth is exactly the pose I struck when I realised what I had done!
Oh Jessie....I'm feeling your pain!!!!! and despair!!!!!
I tried cold water, dish detergent, a washing powder paste, stain remover, vinegar, screaming and lastly, after consulting with Mr.Google.... rubbing alcohol/hand sanitiser. You're right Bodgeitandscarpar..........whiteboard marker needs a high alcohol content to dissolve the ink even when you treat it straight away. So yes, the rubbing alcohol was "the go". BUT, it took several hours of wet compresses of the stuff placed over the marks and changed every half hour or so, with periodic dab, dab, dabbing at the marks. Slowly the marks finally started to fade to the point that now, at a glance, you can't see them and once I've quilted the thing I doubt it will be very obvious thank goodness.
The rubbing alcohol evaporated and the fabric dried fairly quickly once I stopped with the dab, dab, dabbing (and the mutter, mutter, muttering) and as the quilt is pin basted I was loathe to wash the thing so I just gave it a gentle pat with a clean wet cloth to rinse it an itty bit and have left it to dry. Today and tonight is blistering hot so I suspect it is already dry....will check when I can dare to enter the sewing room later...man that rubbing alcohol is sooooo perfumed....bleuh...even with the window open and the fan going...ick...it's going to be a few days before i venture happily in there! It will be washed when the quilting is done and I am loathe to wash a quilt when it is only partly quilted....call me a sook but one scare today is quite enough.
What a blooming nightmare! And you know I have no one to blame but me, I was the numpty that put the sodding whiteboard marker in my fabric marker box by mistake. And bless Mr.Ruby...when he walked in the door this evening and saw me already happily enjoying an adult beverage he smiled and said "how was your day dear?"