Firstly, and just to save any possible confusion down the line... the box you're looking for isn't a TiVo V6, it's just a V6. It runs TiVo software but "common parlance" is a V6.
Secondly, do you have VM broadband? Whilst the TiVo has an in-built modem for all the online bits, the V6 doesn't - and so VM broadband is a requirement.
With those two in-place, there's no formal swapout programme per-se, and the most reliable method is to try to negotiate a box-swap as part of a new package deal. In other words - look at your whole TV/broadband/phone package and see if a current bundle deal is more cost-effective to take as part of a new 18month contract to also include a box-swap. You're best off looking at your current contract/bills via "myVirgin Media" and then comparing it with the standard pricing on the bundle builder site. Pitch yourself at a small discount on the standard pricing, in exchange for the 18month contract & box-swap. Ignore the references to 360 on this page, that's for new customers - but do be aware of.....
.....Also be aware, a C/S agent may offer you a swap to the 360 box instead. This is the same physical box hardware as the 360, but completely different software. I'm not passing any lengthy comment on the pros & cons, there's been enough threads on that already and I'm not starting another one. Suffice to say that it's different, and a conversion to 360 (should you choose) is a one-way trip and is voluntary. While the 360 does have some new features (such as voice control) some TiVo/V6 functionality (mainly around the recording & series-link piece) is currently missing. So do your research and if you do want to go down that route, do so on an informed basis.
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