If that "2 kms" is from the exchange and you are NOT on an EO (Exchange Only - ie directly connected without an intervening PCP cabinet), then you could have distance/attenuation problems.
However, if there is a PCP (oldish Green Cabinet usually), then it would be that shorter distance to your house, which has the potential of higher VDSL speeds.
Assuming that you do have a PCP and the general fibre upgrade is done conventionally as has happened to over 90% of the present "Superfast Fibre", with an FTTC (VDSL) Cabinet nearby, you would have to add in that PCP to FTTC distance.
The fibre will go to the FTTC, new copper links will be added from the FTTC to the PCP, joined to your existing PCP to house via "old copper" wiring.
The way it is done, is to maintain existing phone services including alarms, 999 calls etc, even if you rarely or never use a land-line telephone. Legal requirements etc.
In the meantime, you should ensure that you are getting maximum performance from your present arrangements, particularly making sure that your phone line is "quiet" by doing the 17070 QLT Test, cleaning/tidying any internal extensions etc.