Related על תרומות 3:6

One who takes terumah before first fruits, first tithe [before] terumah, or and second tithe before first tithe, even though he transgresses a negative commandment, what he did is done. [If he prematurely took] first [tithe], it may not be eaten before second [tithe] is taken out of it. [If he prematurely took] second [tithe], it may not be eaten before terumah is taken out of it. And terumah does not prevent the the giving of first fruits. Similarly, [if] one makes starter dough from untithed produce, whether he took challah before terumah, or whether he took terumah before challah, what he did is done. Challah may not be eaten before terumah is taken out of it, and terumah may not be eaten before challah is taken out of it.