As noted, le-khatĥila, all the blessings should be recited as close as possible to the time one wakes up, and it is not necessary to say them specifically after dawn. Therefore, one who arises before dawn in order to work or learn, or for any other purpose, must recite Birkhot Ha-shaĥar immediately upon waking up. However, Birkhot Ha-shaĥar may not be recited before ĥatzot. Therefore, one who wakes up before ĥatzot must wait until after ĥatzot, and once she relieves herself, she recites Al Netilat Yadayim as well as the remaining Birkhot Ha-shaĥar. If she recites them before ĥatzot, she does not fulfill her obligation (the time of ĥatzot, or midnight, fluctuates depending on location and season; most locales have calendars specifying the relevant times; MB 47:31, Kaf Ha-ĥayim 29; Peninei Halakha: Prayer, ch. 9 n. 4; above 5:4.)
One who wakes up after ĥatzot for a few hours with the intention to go back to sleep until morning should say Birkhot Ha-shaĥar after her main waking. If her main waking is the one in the middle of the night, and her sleep after that before morning is like a nap for her, then it is then best that she recites Birkhot Ha-shaĥar after her initial waking. However, if her main waking is in the morning, she must recite Birkhot Ha-shaĥar after the second rising. 1 That is the way she should practice regarding Birkhot Ha-Torah as well (see below 7:7).
- That is the opinion of most poskim and this is the halakha. However, one who wishes to study further will note in Peninei Halakha: Prayer, ch. 9 n. 5 that according to the kabbalists it is preferable to recite Birkhot Ha-shaĥar after the first waking. Someone who is afraid that she might forget to recite the blessings after the second rising, despite the fact that this is her main waking, may rely on the poskim who permit her to recite the blessings after the first time she wakes up. However, as a general rule, when there is disagreement among poskim who rule according to halakha and the kabbalists, practice follows the poskim, except for individuals who follow the Kabbala in all aspects of their lives. ↩