@anarcat the ALL4781-VDSL2-SFP specifications are listed here. If overlapping with the ISP network standards it should work, e.g. G.993.2
Bell has recently started to deploy Alcatel-Lucent 7330 remote SLAMs which do conform to ITU G.993.2 spec and customers served on those are able to use standard VDSL2 modems.
My own experience with this device here