What did Queen Margaery's letter to her grandmother Olenna Tyrell mean?

With all the twists and turns that we are seeing on Game of Thrones season 6, there were many scenes that stood out. One of them was Queen Margaery Tyrell’s suppposed walk of atonement that did not take place, and the events that followed after it. We saw Margaery standing ready for the atonement of her sins, but in a turn of events, we also saw King Tommen emerging to announce the alliance of the Faith and the Crown. This absurd plot twist was brought about by none other than Margaery Tyrell, who was under imprisonment along with her brother Loras (who is yet to be freed). Margaery, through her display of repentance and surrender towards the High Sparrow, managed to win his trust and also convinced her husband, King Tommen, to join hands with the Faith of the Seven.

It seemed that Margaery entirely dissolved all hope for the eradication of the High Sparrow and his other little sparrows who have been wreaking havoc in the lives of the people of Westeros, but soon the real picture started to get clear when Margaery’s unmistakeable cunning nature resurfaced.

After her return to from the prison of the High Sparrow, Margaery was given a subtle hint by the Sparrow that said he might just throw her grandmother, the Queen of Thorns, Olenna Tyrell into one of his cells. Margaery, immediately picking up on this veiled threat, left to see her grandmother, whom she quietly instructed to leave King’s Landing. Olenna Tyrell could hardly believe that her granddaughter had turned into one of the pawns of the High Sparrow, but her sadness and horror soon emanated when Margaery secretly handed her a small letter.

Margaery could not have told her grandmother anything directly, for Septa Unnella suspiciously guarded the Queen’s every move. With her quick wit and notorious nature of getting her way every time, Margaery managed to slip her grandmother a note, which contained the drawing of a rose. The rose, which is a symbol of Highgarden, gave a message which was understood by Lady Olenna as soon as she saw it in solidarity. Although this cryptic message is not revealed, we can assume that it refers to two things.

First of all it showed Olenna Tyrell that Margery was still a Tyrell at heart, which reassured her that there was nothing to worry about Margaery as she might have some plan in her mind and it also hints at Loras Tyrell, who is known as the Knight of the Flowers and is still in captivity. The message could possibly mean that Loras, might just be rescued by his sister through her cunning tactics.

We might not know the exact meaning of the note, but we can certainly say that Margaery is, in no way, under the control of the Faith. It now seems that the Queen is planning something brilliantly devious to get back at the High Sparrow.

Tell us in the comments what you think Margaery might be up to.