This is an interesting halachic question.
In such a case, a
veset haflagah takes precedence over a
yom hachodesh. Meaning, even though you should have established a
veset kavua for the
yom hachodesh on the 7th, this period only reactivated the 30-day
haflagah. Therefore, you will only observe the 30-day
haflagah for now, as it is your
veset kavua. The
yom hachodesh of the 7th of the month was not established as a
veset kavua and you do not have to observe that
veset nor be concerned about it being reactivated in the future.
While in some cases it is possible to establish two separate
vesatot kevuim, in this situation you only have to be concerned about the 30-day haflagah.
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B’Hatzlacha!