Whitlock in Devon brickwall

[Pinefamily]

Hello,
I am really stuck on this one.
I have Ann Whitlock married to Rev. William Palmer in 1743 in Luppitt Devon. Also in 1743 in the same parish was Mary Whitlock married to Richard Harward. Both of these men were from the higher levels of society; the Palmer's had an entry in Burke's Landed Gentry 1847.
Through a couple of wills I have discovered that there were four sisters: Ann, Mary, Grace and Joan. James Townsend was a lawyer whose will left property and money to Joan Whitlock who died unmarried in 1779 and was executrix of his will.She is transcribed as Whitcombe but there is a Devon will corresponding.
Thomas Tucker of Luppitt left a will in 1740 where he left property and money to all four of them, describing them as now living with him, and as Whitlock but lately or now known as Loader. They are also described as daughters of Hannah Whitlock singlewoman.
I can't see any one called Loader in and around Luppitt so I'm not sure what it means. I understand that singlewoman can also mean a previously married woman in this era. But why would Thomas Tucker leave so much to them if there was no family connection or at least in trust mentioned in his will? Could they have been his either illegitimally or by surrogacy? He seems to have been married but no children are mentioned in his will. Given the three sisters married well makes illegitimacy unlikely in my view, but I'd appreciate others' thoughts.
I am also seeking help in finding baptisms for them (none in Luppitt), and also anything on Hannah Whitlock.
Thanks in advance.

[Phoenix]

This document in the National Archives might explain their relationships:

Short title: Whitlocke v Wyatt. Document type: Bill and two answers. Plaintiffs: Joan...


Reference: C 11/1861/18
Description:

Short title: Whitlocke v Wyatt.

Document type: Bill and two answers.

Plaintiffs: Joan Whitlocke alias Joan Loader, Mary Whitlocke alias Mary Loader, Ann Whitlocke alias Ann Loader, spinsters of Luppitt, Devon, Edward Harrison alias Edward Shepard, yeoman of Luppitt and Grace Harrison alias Grace Shepard his wife (formerly Grace Whitlocke alias Grace Loader).

Defendants: John Wyatt and John Flood.

Date of bill (or first document): 1742
Note: The naming of a party does not imply that he or she will appear in all the documents in this cause (after the bill)
Date: 1742
Held by: The National Archives, Kew
Legal status: Public Record(s)
Language: English
Closure status: Open Document, Open Description

[Pinefamily]

Thank you Phoenix. Yes, I have seen that in TNA catalogue. How to access it is the key. I live in Australia, so my options are limited.
From what I know in Thomas Tucker's will, John Flood is his nephew, so I assume that this document is a land transfer. People often transferred land via a court case, to avoid taxes.

[kiterunner]

I don't think there would be a plaintiff if it was a land transfer.

[Pinefamily]

Possibly. It could be a squabble over their inheritance. John Flood was to inherit if the girls died. Perhaps he took some of the property for himself. The sisters are described as minors in the will written in 1730; a codicil attached in 1739 mentions Grace as married.