You are in a bad spot mate, £1600 every 4 weeks is a big loss, BUT those days are already gone, as its now a £480 job/s. Because i also doubt they would revert the prices back the normal once this has all blown over say april/may 21? As their tighter budgets could run for a few years after this? Nature of the beast with commercial work, it can pay well, but if you loose a few you notice it. Unlike domestic work, if you drop a job or two in wont even make a dent, like the above guys say 'eggs in baskets' . IF, i really had to, i would carry on for now, and speed through the work and just give them a £60 job, whilst working very hard on finding other work to replace this now, white elephant. Good luck m.