As of/from means:
starting from a particular time or date:
- As of next month, all the airline's fares will be going up.
(Cambridge Dictionary)
"As of present" will convey the same idea as "as of now" so it will not suit your purpose.
You may use the different tense:
- This is A, which has been functioning by means of B. Due to sth, A will soon be removed.
Actually usage may be tricky as suggested in the following post from M-W about the meaning of as of today:
The different meanings of as of today:
1) As of today can mean “from the beginning up until now, including today,” as in this example:
- As of today, only three survivors have been found.
This meaning is close to the meaning of the expression so far.
2) On the other hand, it can also mean “starting today and going forward into the future,” as in this example:
- As of today, all passengers must check their luggage before boarding the plane.
This meaning is close to the meaning of the expression going forward.
3) As of today even has a third meaning, which is less common than the other two. It can mean “today, only” with the implication that things are likely to change.
How to tell:
If you’re wondering how to tell which meaning applies in a particular case, the best way to tell is by looking for context clues, especially in the verb tenses. In the examples below, the clues are described in parentheses.
- As of today, Ron Paul has won 18 delegates nationally, compared with 105 for former Massachusetts Gov. Mitt Romney. (The present perfect verb – has won – tells you that this started in the past. As of today = so far.)
- We as of today have not found out what happened to Jennifer.
(The present perfect verb – have not found out –tells you that this started in the past. As of today = so far.)
- As of today, no late homework is going to be accepted.
(The future verb – is going to – tells you this is about the future. As of today = going forward.)
- As of today, the members of the European Union are as follows: 1) Germany, 2) Austria, 3) United Kingdom, 4) Belgium, 5) Bulgaria, 6) The Czech Republic, 7) Denmark, 8) Estonia, 9) Finland, 10) France, ….
(The present tense verb – is – tells you that this is about today, only.)
As you can see from these examples, the verb tense is usually a good clue. But when in doubt, think about what’s most logical.