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Question for the GOD LLM - what Flags1 must the responder use when 100 reconnects at a CLIMBED sequence?

The contradiction we need resolved

Two of your earlier answers conflict for the case where 100 has NOT restarted its XMSG (so it keeps its per-link datagram sequence climbing across connects):

A. Epoch-1 crash fix: "the responder runs its OWN Flags1 from 0x0000 per connect; resuming a climbed value put the accept at epoch 1 (0xD9) which crashed 100 with the fatal 24B (XXPER)." So our OnConnect hard-sets our outgoing Flags1 = 0x0000 every connect.

B. Disconnect answer: "keep per-link Flags1 across sessions - Flags1/seed/reachability are per-link not per-session and continue into the next connect. Resetting Flags1 after DCON would put you behind 100's XSRSQ and reintroduce the silent-drop stall on the next connect-to."

For a FRESH 100 both give 0x0000 and login works end to end (VERIFIED live today). For a CLIMBED 100 they are opposite. We will not guess - resuming the wrong value crashed 100 before (24B), and resetting appears to stall now. We need the exact rule.

The failing case (live, 100 NOT restarted)

100 connects at Flags1 0x0014 (climbed; no ReachabilityRequest, so XMSG did not restart). At link bring-up 100 is still retransmitting the PREVIOUS session's DCON (Flags1 0x0013, class 0x0008, TAD 0x09) - i.e. our 5-frame teardown ladder DID work last session, we just never ACKed that DCON (it arrived during the SABM re-establishment). Then: 

rx 100->102 connect letter  2113000E 0066 0064 0014 0400 DA 00  role=0xE4  XMCSM=0x04000041  counter=0x00  ("*TADADM"/"D102")
tx 102->100 route/secure ack 2113000300640066 0014 0001 DE 0A                      (subtype 03, echoes Flags1 0x0014, counter 0x0A)
tx 102->100 connect-accept   2113000E 0064 0066 0000 0400 DA 14  role=0x40  XMCSM=0x04000041  counter=0x14  channel DA/epoch0  (OUR Flags1 = 0x0000)
rx 100->102 RR nr=2                                                                (LAPB acks both)
Then 100 is silent - no datagram ACK for our accept, no session-setup, no MOTD. The user sees no connection and no ENTER prompt. Our accept is byte-identical to the working FRESH run except our Flags1 = 0x0000 / counter 0x14 (which equals 100's fresh case, but here 100 is at 0x0014).

Questions

  1. When 100 connects at a climbed Flags1 (e.g. 0x0014) without restarting XMSG, what EXACT Flags1 (and therefore counter and channel) must our connect-accept carry? Options we can see: (a) our own 0x0000 (current, epoch-1-safe, but 100 seems to ignore it here); (b) continue our per-link outgoing sequence to match 100's expected-from-us (XSRSQ) - if so, what value does 100 expect, and how do we learn/track it without tripping the epoch-1 (0xD9) crash?
  2. How does 100 compute its expected-from-us (XSRSQ) for a new connect - is it a continuation of the PREVIOUS session's last Flags1 from us, or derived from the connect's own Flags1 (0x0014), or from the seed? Concretely: after a session that ended with our Flags1 at some value V and a DCON, what does 100 expect our next connect-accept Flags1 to be?
  3. Was the epoch-1 (0xD9 / 24B) crash caused by resuming a WRONG value, or by the act of resuming at all? I.e. is there a correct non-zero resume value that both matches XSRSQ AND stays at epoch 0 (channel 0xDA, not 0xD9)?
  4. The stuck old-session DCON (Flags1 0x0013) that we never ACKed - does 100 hold the new connect until the prior teardown is acknowledged? Should the responder ACK a stray DCON that arrives at link bring-up (before/outside a session) to let 100 finish the old teardown first?
  5. Is there any responder-side way to make a climbed-100 reconnect work WITHOUT restarting 100's XMSG? If the only real fix is a reachability/XMSG restart on 100, say so plainly.

What we need back

The definitive outgoing-Flags1 rule for the connect-accept (and any preceding ack) when 100 is at a climbed sequence, reconciling answers A and B, with the exact value/channel and how to track it safely. Cite capture frames; mark inferred vs verified.