Querying my consultant?

That does sound very much like your basal is too high at night; and Lantus does have quite a peak about 3-4 hours after injection. Ideally, if it’s the right dose, you should be waking up no more than 1mmol different from when you went to bed, but it’s not always easy to achieve on injections, although Tresiba is a very stable background insulin. I wake up roughly the same as when I went to bed, but I’m on a pump so can set different rates throughout the night to account for my needs.

Could you change the time of your basal? Lantus has a peak after 3 or 4 hours, if you could time your basal so this peak happens whilst you are awake and you can deal with it, it may help.

Your Dr doesn't want you to wake up with a normal reading at this point I'd say. They are looking for you to run stable and stop the hypos which would do more damage in the long run. It takes time to settle diabetes. I'd give your Doctor time and trust them.

It does sound like basal is too high. I'd never really paid that much attention to basal dosing before getting cgm, but I sure as heck pay a lot more attention to it now.

Getting basal right makes everything else much easier, because you're not then having to adjust with food or bolus shots.

Here's an example, pic below. I'd been getting rises after the last bolus shot had worn off, a strong clue that basal was too low. So I started notching it up a bit, and then I changed to a new vial. That vial seemed to be stronger than the one before (I was sceptical about reports of vials differing in strength, but I've seen so many things now with cgm that I think there is something in it), so I ended up, as the pic shows, with a slow decline, nudging it up with 6g, only for it to decline back down again - again, a strong indicator that basal was too high, so I tailed it back a bit.

The difference in dose size really wasn't that large, between 14 and 17, but the changes made a real difference.

In the long run, sure, 10 to 12 is too high, but I think what he's doing is trying to find the correct basal amount. Basal is meant to hold you steady at whatever level you're at, whether that's 5 or 10. So, as you've been having hypos, he's probably keeping you in a hypo free zone at the moment while you figure out what basal dose is working, once that's established, you can tweak with bolus back down to 5 or 6.

Short spells of higher levels can be useful for maintaining hypo awareness. I tend to run at about 5, but whenever I feel that I'm not that aware of levels dropping below 4, I'll spend a week or two being generally still around 5 but deliberately not correcting for 8s and 9s for a few hours. It's surprising how effective that can be, I'll pick up on drops at around 3.7 that way.