How can I say "not any time soon, but it won't take a long time either"?

I was writing an email to a client about a feature we plan to eventually release, maybe in a couple months, but they want some of the functionality now. I initially wrote:

If there's something else I can do for you, go ahead and let me know. I don't suspect the upgrade will be any time soon.

It sounded like I was saying the upgrade will take a long time, but that's not what I want to imply. I almost wrote:

I don't suspect the upgrade will be any time immediately soon.

...which sounds awkward, and I don't think it's correct. The search results I got for the term support my assumption.

What would be a better way to say "not soon, but fairly soon" in this context?

Another way to say it where it doesn't sound so distantly in the future is to say, "The upgrade will not happen in the immediate future."

(thanks Wesley!)

The upgrade is not imminent.

imminent (adj.) liable to happen soon [Collins]; likely or certain to happen very soon [Macmillan]

If you want, you could add some reassurances to the end:

The upgrade is not imminent, but it's coming.