[PHS-1350] HSpot should report the star tracker Solar Aspect Angle for the target to the user.

- Implication for user: Given that the schedulability of AORs is limited at Solar Aspect Angles (SAA) smaller than -20 degrees (i.e. solar elongation greater than 110 degrees) and extremely limited at SAA smaller than -22 degrees, this is important information for the user on AOR visibility.

[PHS-1157] Visibility calculations of HSpot and MPS differ by up to four days.

- Implication for user: To speed up visibility calculation in HSpot some approximations are made. This though can lead to important differences in the nominal visibility of an AOR reported by HSpot and the real one, as reported by the Mission Planning Software, particularly close to the cusp of permanent visibility. This can lead to users believing that a target is visible when it is not, with important implications for scheduling. Some changes have been made in the algorithms to ensure that the agreement between HSpot and MPS is valid for a wide range of ecliptic latitude.

[PHS-1573] Overheads are wrongly calculated when there are several constraints at the same time.

- Implication for user: An important bug in overhead calculation was noticed when an observing programme has complicated constraints involving concatenations and timing constrints simultaneously. On some occasions a time constraint overhead was being charged more than once on a single concatenation. It is believed that this only affected a very small number of OT1 proposals, for which the time saving after the fix was made has been significant.

- Implication for user: Substantial updates have been made in the On-line help to synchronise it with HSpot and to update information.

[PHS-1593] Change the constraint column convention in PHS.

- Implication for user: Additional constraint columns have been added to HSpot so that different types of constraint can be identified easily by users and HSC personnel without having to open the constraint editor and examine the AORs one by one. HSpot now identifies observations that are Sequenced (S) and Grouped within a particular time interval (G).

This fix is also related to the following two bug reports:

[PHS-1457] AOR overlay fails towards the poles.

- Implication for user: The AOR overlay routine was not using spherical geometry to plot overlays. This meant that, close to the celestial poles, the AOR overlay was giving a totally inaccurate representation of the AOR with respected to the requested position.

[PHS-44] Inconsistent visibility for PACS scan maps

* [PHS-1541] AOR overlay is incorrect for some mini-scan mode AORs

[PHS-1454] HSpot suddenly no longer finds the ephemeris for Pluto.

- Implication for user: There was a bug in the handling of ephemeris files for SSOs that meant that for dates beyond the likely end of helium, an overlay could be requested beyond the end of validity of the ephemeris, giving a misleading error that the ephemeris was not available in HSpot.

[PHS-141] HCSSv0.SCI.2AT: Re-wording of "Retrieve latest proposal from HSC"

- Implication for user: Small update in an HSpot message.

[PHS-163] Changes to 'Proposal Submit' window in HSpot.

- Implication for user: A minor change to a misleading message.

[PHS-1606] Title of HSpot 5.3.x main window and Proposal Submission Tool window should refer to "GT2 Call Phase 1 Version".

- Implication for user: Updates the proposal submission window for the new Call.

[PHS-1631] Please update "Tip of the Day".

- Implication for user: Small change to correct ambiguous information in one tip.

[PHS-1500] co-users of submitted proposals should also be allowed to retrieve the proposal documentation.

- Implication for user: Allows a co-I flexibility to act on behalf of a PI and to see a complete proposal.

[PHS-149] Insertion of PI details in proposal cover sheet from HSpot.

- Implication for user: Mainly an administrative fix for the HSC, allowing the PI's name to be included as a co-I of a proposal.