Question of 'he' vs 'they' in Vayakhel-Pekudei

The double parsha Vayakhel-Pekudei contains a mystery as the work of building the Mishkan, the sanctuary for Hashem’s presence, is described intermittently as done by Bezalel (he) or the artisans, all who are of the wise heart (they).   

Vayakhel starts with the impressive professional resume of Bezalel, repeated by Moshe from what Hashem announced  in the previous parsha Ki Tisa: he is filled with the spirit of God ruach elochim, endowed with wisdom, knowledge and insight, master of dozen krafts, but here he is also picking up a teaching gig 35:34 The ability to teach he placed in his heart…   There are more people involved here, all who are of the wise heart, called upon to work on the Mishkan under the leadership of Bezalel, who is supposed to teach and guide them in this holy work.  36:1 He shall do – Bezalel and Oholiab and every man who is wise-hearted whom Hashem placed wisdom and insight within them to know and to do all the tasks for the work of the Sanctuary – for everything that Hashem has commanded. 

So here is the mystery – the first sentence describing the actual work in progress starts with they and ends with he.  36:8 They made – all the wise-hearted among those doing the work – made the Tabernacle: ten panels of linen, twisted with sky-blue wool, purple wool and crimson wool; with cherubim the craft of a master weaver he made them.

Then the rest of Vayakhel is about what he has done, clarifying in 37:1 that he is Bezalel, who single-handedly did all the work, the entire construction.  In Pekudei 38:22 confirms that Bezalel, so of Uri, … did everything that Hashem commanded to Moses, and with him was Oholiab … From 38:22 to 39 it is all he who does everything, and only at the end of Pekudei we see they again, when it comes to the clothes of the Kohanim,

then again it’s a he, and for the small remainder of Pekudei they complete the Mishkan and bring it to Moshe.  39:1 From the  sky-blue wool, purple wool and crimson wool they made the garments.  39:2 He made the Ephod… 39:3 They hammered out the thin sheets of gold and he cut threads… 39:4 Shoulder straps they made… 39:6 They made the stones… 39:7 He placed them… 39:8 He made the Breastplate…39:10 They set in it four rows of stones… 39:15 They made for the Breastplate chains at the edges by the craft of braiding 39:16 They made two settings of  gold…. It is they in every pasuk now until 39:22 He made the Robe of the Ephod, the craft of a weaver, entirely of sky-blue wool. Then again 39:24-25 it is they who made the pomegranates and bells on the hem of the Robe.  And in 39:26-31 they made all the rest of the holy garments for the Kohanim – the Tunics, the Turban, the Breeches, the Sash, the Head-plate, the crown of sanctity of pure gold, and they wrote upon it ‘Holy to Hashem’.  At the end in 39:32-33 they, bnei Israel, completed the work and they brought the Mishkan to Moshe.  He is not mentioned after 39:22, only they.

So what happened, how in the very first sentence, 36:1 above, ‘they’ switch to ‘he’?  Was it the perfectionism of the great designer who was not able to delegate the work to his reports?  Or was it the realization that every detail of the work was of such high importance that it could not and should not be delegated?  Or were the artisans not at the high enough spiritual level, did not have enough merit to do this work in the beginning and only by the end became filled with the same divine spirit as Bezalel to complete the work together? 

I don't know, to be continued...

Reading carefully, obsessively, both portions through the excruciating details of the construction feels like going through the entire labor in miniature, but it has its reward in coming to the breathtaking scene of the cloud of glory that descends upon the Mishkan and guides Israelites in their journeys – the cloud in the day, fire at night, just like a human soul, guided in turn by cool cloud of reason and fire of passion.