By way of comment on this topic, and others relating to wireless fire systems and loop interfaces.
Apollo loop interface (and other fire alarm loop interfaces) all operate on 868MHz radio frequency. The EMS FirePoint panel operates on entirely different UHF/VHF frequencies. Just because Xpander is manufactured by EMS, do not assume you will get the same range between an Apollo device and the loop interface, as you can get between an EMS device and the EMS FirePoint controller.
Those of you familliar with wireless intruder panels will know that they also operate on 868MHz, and their performance/range in anything other than a 3/4 bedroom house can be very patchy.
Commercial/Industrial buildings (the addressable fire marketplace) by their design and construction can pose challanges for wireless equipment operating on 868MHz, eg steel reinforced concrete walls, floors and stairwells, lift shafts, electronic noise and radio interference generated by electrical plant and equipment.
The Xpander system is extremely well engineered, and I understand it has been extensively field tested. A radio survey test from the proposed location of each device back to the location of the loop interface is essential. As long as it is used for the purposes for which it was intended, ie connecting a limited number of wireless devices to an existing loop in close proximity, you will not have a problem.