And just to explain the legislative context which has informed the strategy adopted by women's rights campaigners. (I've put in italics how it works.)
The Scottish Parliament makes laws in a highly regulated manner, which proceeds as follows:
a) A pre-legislative consultation
Every bill should commence by giving stakeholders a chance to consult on the proposals. It's not unusual to find that this is not highly publicised, so only the few people interested in the subject matter will know or respond.
The previous public consultation which closed on 1 March 2018 was designed to serve the purpose of this pre-legislative consultation for the GRA Reform Bill.
However, although practically no one knew about the consultation, 40% of respondents disagreed with introducing self-id. Additionally, women's rights campaigners made enough noise that the government was forced to acknowledge that there are widespread concerns in a public statement in parliament, that it hadn't consulted widely enough and that it was now offering to listen to those who had concerns.
That it didn't make good on this promise is of course a major criticism of the government, however this does not take away from the success achieved by women's rights campaigners:
The Scottish Government started another pre-legislative consultation, albeit in a different format, to allow those opposed to self-id another chance to express their concerns. AFAIK this is unprecedented.
b) Stage 1
The written responses are compiled into a report by the committee responsible for the bill in question. Witnesses may be called upon to present evidence for the consideration of the committee. Their statements will also be incorporated into the report, which must be attached to the draft bill from then onwards, so that all MSPs can consider all of the relevant information.
(At this point, the committee in question typically calls some of those who submitted evidence for or against the bill to present this in person in a hearing in the parliament. These witnesses may be experts in the subject, or particularly affected by the issue of the bill. This is what happened with the Census Bill for instance and this is when it got very very interesting.)
After this, the Committee then considers both the draft bill and the written and oral submissions received during the consultation and produces a report making recommendations to parliament.
Then the parliament will have a session focusing on the bill, hearing first from the committee and the minister/MSP responsible and then there will be a debate. After that, MSPs decide whether they want the bill to proceed to the next stage or not. They may also send the bill back to the committee to produce another report.
c) Stage 2
This is where the bill is usually scrutinised in every major and minor detail. Changes might be suggested and incorporated. This work may be done in committee, in parliament or in both. Witnesses may once again be called to give evidence.
During the Stage 1 Census Bill debate, I was quite bemused to hear MSP after MSP sharing their bewilderment that this simple 1 A4 page law change had grown into such a massive thing, even at Stage 1. (That comes from not thinking that maybe, just maybe making the sex question a self-id one might be a touch controversial.) Stage 2 of that bill was actually tame in comparison.
d) Stage 3
However Stage 2 was carried out, at this stage, it is the whole parliament again that considers the bill as well as any new amendments introduced at this point. If parliamentarians are not happy, they may send parts of the bill back to Stage 2 to be scrutinised again.
Then the parliament votes on the bill again. If MSPs vote yes, there is a mandatory waiting period (when it may be legally challenged or recalled by parliament) and then the queen signs the bill into law.
If MSPs vote no, the bill falls.
And this process is the one that women's rights campaigners are now focusing on. Convincing MSPs to reject the bill is the best chance we have of stopping this madness. Which is why we're also contacting our politicians to share our concerns, and why everyone should contact theirs even if you're not in Scotland.
P.S. Once self-id is law in Scotland, it will effectively exist in the rest of the UK, too. That's because there is no way to stop a GRC being legally valid once its bearer crosses the border into England. So, please, even if you're not in Scotland try and see your MP to share your concerns.