Under Level 4, unless you are an essential business you are not allowed to go to the office space. Under Level 3 which starts on Monday the 27th of April & for a minimum of 2 weeks there will be a new regime that is more permissive for business to trade, as long as you are able to confidently practice safely with social distancing and being contactless. The assumption is therefore if you work in an office, that you work from and stay home.