Just to put a possible spanner into the works.
Chewing gum on Tarmac is an absolute nightmare and that depends on the type of Tarmac it is and how long it has been down.
Did the storefront at Staines Tesco but I wasn't there. It was done on cold and when I got there it was a mess with overworked areas and with no lifting off between the gum it was squiggled. Looked a right mess. A lot of the gum was not done.
To put it right I had to put the dry steam machine on it, pressure wash it on the flat nozzle, go over it with the FSC and then rinse off.
You can easily put too much heat on Tarmac and it will damage it as it is bringing the gum off . My view is that Tarmac should be done with dry steam, a lot less aggressive. There may be others who will disagree on this detail.
Rob