Word for something that can be obsolete in the future, obsolete-able

You might consider, obsolescence-prone and obsolescent-/obsolete-prone

If you're concerned about the problems of owning or maintaining rundown, obsolescence-prone freight equipment, talk it over with U.S. Railway Equipment Company. Chances are we'll have some interesting dollar-saving suggestions.

During periods when business generally is slumping, the profit picture is helped by the fact that the real estate man need hold no large investment in buildings, equipment, or obsolete-prone products.

Adult Education Through Home Study

Also, planned (or built-in) obsolescence, as in

Planned or Built-In Obsolescence products are designed to fail within a given period of time [...]

prezi.com

planned obsolescence

: a method of stimulating consumer demand by designing products that wear out or become outmoded after limited use. Also called built-in obsolescence.

Random House

Obviable:

capable of being obviated

And since obviate doesn't get the recognition it deserves...

Obviate:

to make (something) no longer necessary : to prevent or avoid (something)

The common thread among your first three examples is that they are verbs. Things that are able to 'do' those verbs may then be suffixed with -able.

This is the same with other words like write (writeable), read (readable), eat (eatable / edible), etc.

Obsolete is not normally considered to be a verb (it's an adjective), so is modified differently (e.g. obsolescence).

The following dictionary entry mentions that obsolete may be used as a verb:

Obsolete verb [with object] chiefly US Cause (a product or idea) to become obsolete by replacing it with something new: we’re trying to stimulate the business by obsoleting last year’s designs - ODO

The form obsoletable may be used in that sense. Here's an example:

Coloring the cards only works for nonperishable and non-obsoletable items. - Manufacturing Consulting Services, Inc

As @PLL notes, obsolesce is the proper verb form of obsolete. Here's the dictionary entry

Obsolesce derived verb (derived from obsolescent: Becoming obsolete) existing systems begin to obsolesce - ODO

It's not a single word, but this meaning seems to exist already as an established term in the business sector: "obsolescence risk"

http://www.investopedia.com/terms/o/obsolescencerisk.asp

Companies can be discussed in terms of their obsolescence risk or "obsolescence factor".

I think that the reason there isn't a word for "potentially obsolete" is that it applies to everything: nothing is immune from becoming obsolete. So, while there are lots of things that are very hard to destroy, hard to consume or hard to do, so we need both words for each of those cases (indestructable/fragile, edible/inedible, possible/impossible), i think there is an implicit assumption that everything is potentially obsolete and so we don't really need a special word for it. Which isn't to say there shouldn't be one.

So it might be that you're actually looking for a word to describe something with a high obsolescence risk/factor, ie that is relatively likely to become obsolete more quickly. I have a feeling that there is a word or term for this: perhaps "not futureproofed"?