LWSElectrical

Hi, I'm after some advice regarding EL in existing premises where there is no EL at present. It's a medium size warehouse (38m X 20m) with polycarbonate roof sheets so plenty of natural daylight apart from late afternoon Nov-Jan. The shifts finish at 17:00-17:30 so EL is only required for 3 months of the year for a couple of hours at most. They have final exits, signage, fire extinguishers etc but no EL at present. The customer says that according to their fire safety "expert" they only need a couple of ELs above the fire exits as the signage is photo-luminescent. Does this sound right or should New EL installations in older buildings conform fully to BS5266-1:2016. They don't want to pay out for a fully compliant install. I'm wondering is it better to do nothing than to not comply and face serious consequences should the worst happen when the EL is needed? Is it acceptable to deviate from BS5266-1:2016 if a risk assessment has been signed and agreed? Thanks in advance for your help